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Bootblock initialization code checkpoints – Acer Altos G520 User Manual

Page 178

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Appendix F: Diagnostic Code Checkpoints

168

Bootblock Initialization Code Checkpoints

The Bootblock initialization code sets up the chipset, memory and
other components before system memory is available. The following
table describes the type of checkpoints that may occur during the
bootblock initialization portion of the BIOS:

B1

R

OFF

R

A

Save system context for
ACPI.

00

OFF

OFF

OFF

OFF

Passes control to OS
Loader (typically INT19h).

Check
point

Diagnostic LED Decoder

Description

G=Green, R=Red, A+Amber

MSB

LSB

Before D1

Early chipset initialization
is done. Early super I/O
initialization is done
including RTC and
keyboard controller. NMI
is disabled.

D1

R

R

OFF

A

Perform keyboard
controller BAT test. Check
if waking up from power
management suspend
state. Save power-on
CPUID value in scratch
CMOS.

D0

R

R

OFF

R

Go to flat mode with 4GB
and GA20 enabled. Verify
the bootblock checksum.

Check
point

Diagnostic LED Decoder

Description

G=Green, R=Red, A+Amber

MSB

LSB

BB!H631!.!FO/cppl!!Qbhf!279!!Uvftebz-!Bvhvtu!28-!3115!!5;13!QN